Normally I’d post a reading list at this time, but my usual help in putting one together is unavailable this week and next. So, you’re on your own. Sorry. In its place, here’s a post based on a paper Aaron drew my attention to.
In a 2011 paper, members of the US Preventative Services Task Force (ungated pdf) explained how the organization evaluates services in general and how it came to its decision about lipid screening for children in particular. The clear message delivered by the authors is that the USPSTF process is nothing if not systematic and transparent, incorporating peer-review and public input, and including a rigorous check for conflicts of interest. In the case of lipid screening for kids, the body concluded that the evidence was insufficient to recommend for or against screening. Consequently, according to the USPSTF, any screening advice, for or against, is not evidence based.
Because the evidence is inconclusive, the authors suggest that a shared decision making (SDM) process be employed to help clinicians decide with their patients whether to screen, consistent with patients’ (or, in this case, probably their patients’ parents’) values. The authors also note that in the absence of an official recommendation, there is great opportunity for research. In fact, before practice patterns are established is the best time for randomized trials. After practice is standardized — whether based on evidence or not — randomized trials might be considered unethical. Observational studies are more difficult when practice patterns are less varied and possibly correlated with unobservable quality. (On this point, related posts are here and here.)
However, in the case of lipid screening for children (and perhaps other tests for which the USPSTF finds inconclusive evidence), there is another organization that is willing to make a recommendation. The American Academy of Pediatrics (AAP) does recommend lipid screening for certain kids. The authors take issue with the AAP’s process by which that determination was made.
The original recommendations by [AAP’s] National Cholesterol Education Program were based on those of an expert consensus panel, in which scientific and clinician experts participated in a commonly used process to arrive at clinical guidelines. As with many expert panels, the methods used to identify and analyze scientific evidence were not explicitly defined in the report. In its subsequent updated clinical reports, the Committee on Nutrition did not reference or outline a clear method for its updated literature review. […]
Because this AAP clinical recommendation appears to have been based on less systematic and transparent methods, users may not know whether the recommendation is consistent with the evidence, whether guideline developers factored in important research gaps when developing the recommendation, or how potential conflicts of interest may have been managed.
To the extent the AAP process is not evidence based (and it is to some extent, but it is hard to tell how), what is it? Let’s call it eminence based, or at least partly so. Does that seem fair? If not, why not? Can you think of a better example of eminence based medicine?